The Marquis, not to be behind the curious and ingenious men of ancient times, has here and in article No. 18, emulated John Muller of Nuremberg, better known as Regiomontanus, who was born in 1436. He is celebrated for this species of _rara avis_; a self-moving and flying eagle, and an iron fly have afforded much matter for romantic and no doubt exaggerated accounts of their performances; the one flying a good way in the open air and returning; the other flying from the philosopher round a table and coming back to his hand. He evinced a genius of the first order as a great inventor, and also as a promoter of the advancement of science. In Ramelli’s great work on various machines, folio, 1588, the 187th figure offers a detailed representation of a handsomely furnished apartment, in which a large carved sideboard sustains a gigantic vase containing a flowering shrub, in the branches of which six birds appear in the act of singing. The vase being a sectional drawing, various pipes can be seen, also the performer behind, who is blowing through a single pipe into the body of the vase. But the highly popular work of Hero of Alexandria promulgated several similar schemes. He shows how to make an artificial bird sing by flowing water, or alternately sing and be silent. See Mr. Woodcroft’s handsome edition of Hero’s Pneumatics, 4to. 1851. William Bourne, also, in his “Inventions or Devices,” 1578, treats of “birds of wood or metal made by art to fly,” and of others, “to sing sweetly at certain hours appointed.” Bate, in his “Mysteries of Nature and Art,” 1635, treats, at page 24, “How to make that a bird sitting on a basis, shall make a noise, and drink out of a cup of water, being held to the mouth of it;” and further, “Advice whereby several voices of birds chirping may be heard.” So again Isaac De Caus, in his “Rare Inventions of Water Works,” folio, 1659, at page 20, gives instructions--“To counterfeit the voice of small birds by means of water and air.” And in Plate XIV. “To represent divers birds which shall sing diversly when an owl turns towards them; and when the said owl turns back again they shall cease their singing.” These later examples show that the Marquis was neither altogether original nor singular in attempting improvements in these automatic toys, which from the time of Hero of Alexandria were accounted sufficiently wonderful evidence of mechanical ingenuity to attract the serious attention of even the most talented engineers of the last century. Of such mechanical achievements of the ingenious a full account may be read in Montucla’s edition of Ozanam’s “Mathematical Recreations.”